Heat exchangers have a wide variety of applications in systems where thermal energy (often simply referred to as “heat”) must be moved from one location to another. Similarly, thermal energy storage (TES) heat exchangers are widely used to temporarily store excess thermal energy and later release the energy. This has the benefit of thermal “load leveling” (duty cycle averaging), reducing the thermal load that must be dissipated. In many TES heat exchangers, a phase change material (PCM), such as paraffin, is used as the thermal storage material in the heat exchanger due to its stability and high thermal storage capacity.